Marking device and method



March 10, 1964 J. w. KRUEGER ET AL 3,124,069

MARKING DEVICE AND METHOD Filed Dec. 28, 1959 Fmm Feed ,QoZZ or Endless five NVENTO 1/ f r ll). 162-1164 United States Patent 3,124,069 MARKING DEVICE AND METHOD John W. Krueger, Cottage Grove, and Jon F. Warner,

Oregon, Wis, assignors to La Salle Steel Co., Hammend, Ind a corporation of Delaware Filed Dec. 28, 1959, Ser. No. 862,121 17 Claims. (Cl. 101-426) This invention relates to a method and device for marking surfaces such as metals, plastics and the like, particularly in a cold finishing operation Where the surfaces of the metal are sometimes coated with a film of an oily or oleaginous material. More specifically, it relates to a method for marking metal pieces without the necessity of making use of separate steps for cleaning the surfaces of such metal pieces prior to their being marked notwithstanding the presence of a greasy film on the surface of the metal of the type which normally interferes with planographic type of reproduction processes or otherwise contaminates the inking system.

Frequently it is desirable to mark various types of surfaces, such as metals or plastics, to inscribe various notations, indicia, trademarks, advertising slogans and the like. In the case of elongated metal pieces it has been customary to provide such markings by utilization of a special type of planographic reproduction process. In such process, the part to be marked is advanced to an offset roller which has received the ink image for transfer onto the surfaces of the piece. The offset roller may have received the ink image from an offset plate, from a type plate or the like.

It has been the experience of the art that when such planographic machines are employed for marking elongated metal work pieces, such as bars, rods, tubing and the like, the parts to be marked must be thoroughly cleaned to remove all traces of hydrophobic substances such as oils, greases, lubricants and the like which may have been applied to or taken up by such pieces during the various stages of operation. If the pieces are not cleaned, the offset roller will pick up hydrophobic materialfor transmission to the reproduction roller. This contamination interferes with the inking process and such greasy substance as is carried back into the inking system interferes with the proper functioning thereof. In any event, reproduction for marking becomes inacceptable for use.

One solution attempted is to employ expensive and complicated cleaning processes and equipment in conjunct-ion with the planographic reproduction or marking device of the type described. Such processes materially increase the cost of operation and require the utilization of valuable space which may not be available where the metal is being processed. Further, such cleaning systems based upon the use of solvents or aqueous medium require care in their handling or in the disposal of fluids and vapors. It would be a valuable contribution to the art if a simple and inexpensive reproduction device and method were available for use in marking surfaces, such as elongated steel bars, tubing and the like, without requiring removal of greasy films or pretreatment or cleaning of the surfaces. It would be a further benefit to the art if it were possible to combine the cleaning of the elongated metal parts and the marking of said parts by a re- 3,124,069 Patented Mar. 10, 1964 production system wherein both the cleaning and reproduction operations are carried out in a simple and efficient operation, requiring little by way of additional materials or equipment.

It, therefore, becomes an object of this invention to provide a means and method for marking such surfaces.

Another object is to provide a means and method for marking elongated metal work pieces by a reproduction system whereby the system is insensitive to the presence of hydrophobic or other oleaginous materials on the surfaces of the metal work pieces.

A further object is to provide a simple method of cleaning and impressing an image onto the surface of an elongated metal work piece by means of a simple planographic type of reproduction device. Other objects will hereinafter appear.

In accordance with the practice of this invention, it has been found that such work surfaces may be suitably marked by a reproduction process which makes use of a tape, preferably in the form of a disposable tape, as a medium for receiving the ink image for transfer to the surface to be marked. In a preferred embodiment of the invention, the tape is formed of a disposable material which, after making the transfer, may be discarded.

In a further embodiment of the invention, the transfer tape has the markings removed therefrom after transfer to enable re-use of the tape as a transfer medium in an endless and continuous system.

In a still further embodiment of the invention, use is made of a' planographic marking system which utilizes a disposable tape fortransfer and wherein the same tape functions to clean the surfaces of the work prior to transfer of the image thereto. In furtherance of this concept, use is made of a new and novel tape having one side usable as a transfer medium and the other side usable as a wiper and means are employed whereby the wiping surface is brought into contact with the surface to be marked for cleaning prior to contact of the surface with the other'side of the tape for transfer of the image therefrom.

In yet another embodiment of the invention, there is provided a special tape which has upon its surface a transferable marking which is protected by an overlay sheet FIG. 1 is a schematic side elevational view of a marking device embodying the features of this invention and wherein use is made of a disposable tape;

' FIG. 2 is a schematic side elevational view of a marking device similar to that of FIG. 1 but in which use is made of an endless tape;

FIG. 3 is a schematic side elevational view of a marking device embodying the features of this invention in which use is made of a premarked tape which is protected during storage and use by an overlay;

FIG. 4 is a schematic side elevational view of a modification in a marking device in which utilization is made of a strip type marking element;

FIG. 5 is a schematic side elevational view of a still further modification in which a tape functions sequentially to engage the surface to be printed with one side for cleaning and the other side for transfer of the image thereto, and

FIG. 6 is a perspective View of a segment of a tape which is particularly adapted for use in the device shown in FIG. 5.

The invention will hereinafter be described with reference to the marking of surfaces of steel bars and rods which may have an oil or other oleaginous film on the surfaces thereof and which usually interferes with transfer of an ink image thereto for marking and which transfers back oleaginous material to the ink roll to raise problems in ink transfer. It will be understood that the concepts hereinafter described will have application to other work pieces posing similar marking problems.

In FIG. 1, illustration is made of a letter press process for transfer of ink composition 12 from an ink well 14 to the surface of the type 16 mounted on the periphery of a marking roll 18. For this purpose, an ink roll 20 mounted for rotational movement upon a shaft 22 is partially immersed in an ink bath in the ink well. The ink composition picked up on the surface of the ink roller is spread over the surface by one or more spreader rollers 24. The marking roll 18 is also mounted on a shaft for rotational movement in a direction opposite that of the ink roll and spaced therefrom by an amount to bring the face of the type in surface contact with the inked surface of the ink roll for transfer of ink composition from the ink roll to the type face. Ink composition is transferred from the type face to the adjacent surface of a tape 26 formed of disposable material as the tape is advanced from a sheet roll 27 mounted for rotational movement upon a shaft 29 into the nip between the marking roll 18 and an impression roller 28 mounted for rotational movement on a shaft 30.

The impression roller 28 is positioned to press the surface of the tape into contacting relation with the inked type face as the tape passes therebetween whereby ink composition transfers from the type face to the surface of the tape. The impression roller, which turns in a direction opposite the marking roller, is also positioned to press the tape onto the adjacent surface of the work piece 32 as it is advanced linearly over the surface of guide rollers 34 by means of a drive roller 36 located either in advance of or beyond the impression roller. The drive roller operates to effect linear displacement of the work piece at a speed corresponding to the peripheral speed of the impression roller or the linear speed of travel of the tape whereby the ink image on the tape is brought into contacting relationship with the surface of the work piece as the tape travels between the impression roller and the surface of the work piece to transfer the ink image thereto.

The disposable tape is made available from a feed roll 27 mounted for rotational movement upon shaft 29 and the spent tape is taken up on a roller 42 mounted for rotational movement on a drive shaft 44. One or more tensioning rolls 46 may be provided to maintain the desired tension in the tape and the tape is adapted to be displaced by the impression roller for movement at the same linear speed as the roller and the work.

Since the tape is brought into surface contact with the work only once and thereafter disposed of, the removal of oil, lubricant or other oleaginous material from the work onto the tape will have no effect upon the image or upon the inking system thereby to permit free and continuous operation.

In FIG. 2, the tape 26 is in the form of an endless strip that is threaded about the impression roller 28 and a drive pulley 50. The tape receives a transferable ink image in the same fashion as illustrated in FIG. 1. After the image on the tape has been pressed into surface contact with the surface of the work for transfer of the image thereto, it is advanced to a wiper 52 for removal of the image from the surface whereby the tape may again be cycled through the system for use.

In smaller plants or in instances where a limited number of work pieces are to be marked, it is sometimes desirable to employ a premarked tape 26 which is advanced to the work 32 and the impression roller 28 for impressing the marked surface onto the work for transfer. This embodiment of the invention is illustrated in FIG. 3 where a premarked tape 26' provided with an overlay strip 60 is positioned on a supply reel 62 and is brought into surface contact with the work piece by means of the impression roller 28. The overlayis placed on the tape during its preparation for purposes of permitting the tape to be wound upon the reel 62 without disturbing or transferring the image thereon. The overlay 60 is stripped from the printed surface of the tape immediately prior to use by means of a winding roll 64 positioned adjacent the impression roller 28.

In FIG. 4, the tape 26 is shown as receiving a transferable impression on one surface thereof by the expediency of a reproduction device, such as a letter press or a gravure type of reproduction system. This impression of the tape with the transferable marking is not specifically shown but is generally represented by the element 70. To those familiar with the graphic arts, 72 would be a letter press, a mimeograph machine or like imaging device which would be capable of transferring an image to the surface of the tape, which image would be capable of being offset from the tape onto the work piece 32 by means of the impression roller 28. The tape 26 is tensioned by means of idler rollers 46 and 48 respectively.

In the construction illustrated schematically in FIG. 5, the tape 26 positioned on the supply reel 37 is of the type which is adapted to be printed or imaged on one side with a transferable material while the opposite side 82 embodies the characteristics of a wiper. The tape 26" is advanced from the feed roll 37 through the guide rolls 94 and 96 into the bite between the impression roller 28 and the surface of the work 32. The image preprinted on the surface 80 of the tape or applied to the surface, as by the processes previously described with reference to FIGS. 1, 2. and 4, is transferred from the surface of the tape to the work as it passes between the impression roller and the work surface. As the tape leaves the impression roller, it passes over guide rollers 54 and 56 and thereafter about the wiper wheel 96. By positioning the guide rollers 54 and 56, as shown in the drawing, the opposite or wiper side 82 of the tape is brushed against the surface of the work in a direction opposite the direction of movement of the work whereby it performs a cleaning operation to remove oleaginous and the like materials from the surface of the work in advance of transfer of the image thereto. Thereafter, the tape 26" is wound about reel 100 to be discarded. In this embodiment, the tape operates in a dual capacity of both cleaning the work surface prior to marking and then marking the surface which has previously been cleaned.

The work piece 32 can be used as the driving means for the marking mechanism as by the use of a take-off roller 102 in operative engagement with the work surface. The take-olf roller 102 is connected to the impression roller by a belt 104- operative by the pulleys 106 and 108 secured to the take-off roller 102 and impression roller 28 respectively.

When devices of the type shown in FIG. 5 are utilized in marking various types of elongated pieces of work which may contain hydrophobic surface contamination which tends to smear the final markings thereon, it is expedient to use a special tape of the type shown in FIG. 6. The special tape 26" has one face 80 which embodies the characteristics of a transfer surface while the other face 82 is formed of a porous or absorptive material to aid in removing hydrophobic substances from the work piece prior to being marked. Since two types of surfaces.

are needed, such surfaces may be provided of two different materials bonded together with a suitable hydrophobic barrier 112, such as polyethylene, glassine or the like substance being interposed between the two layers.

While the invention has been described generally, it will be understood that many modifications in the arrangement and construction of parts may be made without departing from the spirit of the invention. While the devices shown are described with particular emphasis on the cleaning of elongated metal work surfaces of the type containing hydrophobic or oleaginous contamination, it will be understood that the concepts of the invention are applicable to other surfaces such as all types of solid plastics as well as glass and other similar type relatively non-porous surfaces.

The tapes used in the devices described are preferably disposable and to that end are most satisfactorily produced using plastics, paper or other cheap but disposable material which is capable of receiving a transferable marking. When an endless tape is used, a more sturdy material, such as heavy plastics, thin metal, leather and the like may be used to provide a degree of permanency to the installation. The coating medium for treating the paper to impart thereto a transferable marking may be suitably selected from any number of well known substances which for the most part are lithographic type inks. Thus, such commercial offset marking inks as those made by James H. Matthews Company may be utilized. By way of further illustration, use can made of inks formulated with Luxol Fast Red BB, Nile Blue BXA Basic or Oil Blue CSP.

The mechanisms and principles herein involved present a solution to a problem which has long vexed those concerned with the imaging of elongated pieces of metal whereby it is desirable to have clear, legible markings thereon with a minimum of maintenance required to keep the marking machines in good working order. Since the tape contacts the surface only one time, the buildup of contaminants on the reproduction device, when such is employed, is eliminated. By utilizing the practices of this invention, it is possible for those in the steel industry to mark elongated metal work pieces without having to resort to the use of complicated printing machines and cleaning processes and equipment.

In summation, it will be apparent that we have provided a means which obviates difficulties encountered previously in the marking of metal parts wherein use was made of an offset wheel which became dirty in use and thereby functioned to interfere with the operation of the ink transmitting system and the reproductions secured therefrom. The concept of this invention resides in an ofiset wheel of an effective infinite circumference which is incapable of returning soil or ink into the printing system by providing an outside wheel rim which makes use of a tape of infinite length which Wraps around the wheel and then is either removed or discarded to eliminate return of dirtiness to the ink system to cause smearing.

Having thus described our invention, what We claim is:

1. The method of marking moving surfaces by an offset reproduction process which comprises cleaning the surface prior to its marking with one side of a moving tape, imposing a transferable marking on the other side of the tape and moving the marked portion side of the tape in contact with the surface.

2. The method of claim 1 where the marked side of the moving tape contacts the surface before the reverse side cleans the surface.

3. The method of claim 1 'where the unmarked side of the tape moves in a direction opposite to the movement of the surface.

4. The method of claim 1 where the tape is disposable.

5. The method of marking the surface of an elongated piece of metal stock by a planographic reproduction process which comprises cleaning the surface of the stock while it is advancing with one side of a moving tape, imposing a transferable marking on the other side of the moving tape, contacting the cleaned side of the advancing metal stock with the marked side of the moving tape and transferring at least a portion of the markings to the surface of the metal stock.

6. The method of claim 5 where the marked side of the moving tape contacts the advancing metal stock before the reverse side cleans said metal stock.

7. The method of claim 5 where the unmarked side of the tape moves in a direction opposite to the movement of the metal stock.

8. A device for marking surfaces comprising a tape containing on one side thereof a transferable marking, a supply source for said tape, means for moving the marked side of the tape into contact with the surface, and means for contacting the surface with the unmarked side of the tape prior to its contacting the marked side thereof.

9. The device of claim 8 where the tape is marked with a transferable ink.

10. A device for marking elongated metal pieces comprising means for advancing said metal pieces in a linear plane, a tape, one side of which contains a transferable marking, a supply reel for said tape, means for contacting the marked surface of the tape with the advancing metal stock, means for reversing the sides of the tape, and means for contacting the unmarked side of the tape with the advancing metal stock prior to its contacting the marked side of the tape.

11. The device of claim 10 where the tape is disposable.

12. The device of claim 10 where the tape is moved in response to the advancement of the metal stock.

13. The device of claim 10 where the means for contacting the marked surfaces of the tape with the advancing metal piece is an offset drive wheel.

14. The device of claim 10 where the means for contacting the unmarked sides of the tape with the metal piece is a Wheel.

15. The device of claim 10 where the means for contacting the unmarked portion of the tape with the metal piece moves said unmarked side in a direction opposite to the movement of the metal piece.

16. The method of marking moving surfaces by a planographic reproduction process which comprises providing a reel of tape capable of receiving transferable markings on one side, said tape also having an unmarked side, continuously unreeling said tape and applying a transferable marking on said one side of the tape, pro viding an impression roller adjacent the point of movement of said moving surfaces, passing said tape between said roller and said moving surfaces with the marked surface of said tape in contact with said moving surfaces, separating said tape from the surfaces immediately after transfer of said marking, and passing said unmarked side of said tape into contact with said surfaces prior to contact with said one side whereby said unmarked side serves to clean said surfaces.

17. The method of marking surfaces of metal bars and rods (hereinafter referred to as bars) the surfaces of which are covered with a film of oleaginous material, without the need for previously cleaning the surfaces of the metal bars for removal of the oleaginous film, comprising the steps of advancing the metal bars continuously in one direction, advancing an endless tape at the same linear speed as the metal bars, bringing one surface of the endless tape into contact with an inking roll whereby an ink impression corresponding to the mark is transferred to the one side of the tape, bringing the endless tape into surface contact with the metal bars while traveling in the same direction for passage together beneath a compression roller with the tape located between the compression roller and the metal bar and with the surface 7 8 having the ink impression on the side facing the bar References Cited in the file of this patent whereby the tape picks up oleaginous material from the surface of the bar while the bar receives the ink impres- UNITED STATES PATENTS sion from the surface of the tape, and thereafter ad- 1,349,807 De Brayer 171 1920 vancing the tape in a direction away from the bar to 5 210961731 Cast) et a1 26, 1937 separate the tape from the bar whereby the tape, the sur- 2,186,788 Olson 1940 face of which is wet with the oleaginous material, is 2,255,953 Vergobbl P 16, 1941 incapable of being re-inked and is therefore discarded, 2,543,281 Bartholomew P 10, 1951 while the bar becomes marked through the oleaginous 2,700,629 Townsend Jan. 25, 1955 film. 10 2,887,051 Maunder May 19, 1959 

1. THE METHOD OF MARKING MOVING SURFACES BY AN OFFSET REPRODUCTION PROCESS WHICH COMPRISES CLEANING THE SURFACE PRIOR TO ITS MARKING WITH ONE SIDE OF A MOVING TAPE, IMPOSING A TRANSFERABLE MARKING ON THE OTHER SIDE OF THE TAPE AND MOVING THE MARKED PORTION SIDE OF THE TAPE IN CONTACT WITH THE SURFACE. 